Ball point pen



Nov. 27, 1962 A. FEJES BALL POINT PEN Filed Dec. 29, 1958 FIG. 3

FIG!

FIG. 2

3,fifi5,732 Patented Nov. 27, 1962 3,l65,732 BALL lPQliNT PEN Anton Fates, Munich, Germany, assignor to Adolf Bergiein, Munich, Germany Fi led Dec. 29, 1958, Ser. No. 733,613 '7 Ciaims. (U. Mililin) This invention relates to ball point pens. More particularly, this invention relates to improvements for the writing medium (e.g. ink) chamber of ball point pens.

An object of this invention is to provide a novel and useful valve closure for the writing medium chamber of ball point pens for air access to the chamber only when the pen is being used.

Another object of this invention is to provide valve and valve operator arrangements peculiarly adapted for use in a ball point pen having an outer casing containing and holding a unit comprising a separate tubelike writing medium chamber connected to a ball point writing end.

This latter unit is known in the art as a refill.

Another object of this invention is to provide a partition for separating a ball point writing medium chamber into two or more sections with restricted writing medium flow between the sections for the purposes pointed out below.

The flow of writing medium from the writing medium chamber to the bail in the writing end of a ball point pen depends primarily upon gravity. Gravity is assisted somewhat by capillary action in the tubelike chamber containing a column of writing medium. However, when the ordinary ball point pen is used in a position where the writing end or point is above or nearly horizontal with the writing medium chamber, the lack of gravitational flow or the gravitational pull away from the writing end will soon overcome the capillary forces and cause the flow of writing medium to the ball point to stop.

it is an object of this invention to provide a partition in the writing medium chamber so that the ink or writing medium flow backwards from the Writing end is restricted and the column of writing medium therein is effectively severed to minimize cohesion atrthe partition and thereby restricting gravitational flow of writing medium from the section of the chamber forward of the partition.

In order to prevent formation of a partial vacuum and theresultant restriction of How in the writing medium chamber of a ball point pen, some form of air or atmosphere access to the chamber must be provided. Since free access to the chamber permits possible writing medium leakage, evaporation of the writing medium or damage to the writing medium by oxidation or the like, only enough air access should be provided to prevent a partial vacuum intermittently operating inlet valves have been previously proposed to fulfill this function, but their operation hasbeen inadequate. Improper valve action and complex and non-adjustable arrangements i have led to valve leaks and malfunctioning.

Accordingly, it is an object of this invention to provide avalve arrangementvand. construction that overcomes theseinadequaciesandwhich .is unusually simple and inexpensive to fabricate, particularly for mass production.

These advantages are obtained by provision of a ball point pen refill. having a valve as hereinbefore described in which thevalve closure includes a spindle valve guided in a straight line within the. tubular writing medium cham- .ber, a, spring yieldingly holding the valve in closed position, a'valve seat for the spindle valve made by deforming the refill tube, a guide member connected to the spindle valve for guiding'it in and out of seated postion, the guidemember'being slidably mounted in the refill tube for this purpose, air inlet means, between the refill point pen casing acting upon the guide member and spindle valve in a direction to open the valve against the valve spring. A valve seat is formed by a bead-shaped boss on the refill tube. The spindle valve includes a valve disk and a threaded spindle, the latter being adjustably connected with a guide member which serves both as a seat for the valve spring and a guide for the valve.

Further, in obtaining the above-mentioned advantages, one or a plurality of cross section reduction means is provided to subdivide the writing medium chamber into two or more restricted passage sections. Preferably, 'a restriction is placed across the chamber fairly close to the forward writing end to provide a small chamber close to the writing end with a second larger storage section to the rear of the restriction. It can be seen that the same bosses used to form a valve seat or used as a spring seat may be also formed in such a manner as to restrict the flow through the writing medium chamber. The cross section reduction means may be formed as a partition inserted into the refill tube. This partition is provided around its circumference with capillary longitudinal grooves for delayed passage of the writing medium.

With regard to the valve arrangement, the operation of the pens prepared in accordance with this invention is as follows: When the ball point of the pen is pressed against the paper, the casingof the pen and the valve seat thereon are moved rearwardly with respect to the pen casing against the spring or biasing means and the spindle valve and guide or guiding member are prevented from movement relative to the casing by the casing detent. Thus the valve is actuated to open position to allow air to enter into the tube or writing medium chamber. So long as the pen is pressed against the paper the valve will'remain open and the writing end will be resiliently held against the paper by the valve spring. I

Further details of the invention are described in the following specification with reference to the accompanying drawings which illustrate an embodiment of the ball point pen refill according to the invention. v

FIG. 1 shows a longitudinalsection, partly in side elevation, an embodiment of a .ball point pen refill with valve closure and some parts of the surrounding ball point pen casing,

FIGURE 2 shows a longitudinal section, partly in side elevation, another embodiment of the ball point pen and refill, and

FIG. 3 shows in same illustration as in FIG. 1a further embodiment of the ball point pen and refill.

In FIG. 1 the reference numeral 1 represents the refill tube or shell with the front writing end 2, provided .in known manner with the writing ball point. On the rear end of the shell 1 the valve closure is provided, which includes a spindle valve with a conical valve disk 3, a conical valve seat 4 obtained by a bead-shaped embossing of the refill shell 1, a valve closurespring Sand cylindrical guide member 7 for said valve rigidly connected to the spindle 6 of the disk valve 3. Guide member 7 is loosely guided by the refill shell 1 in its longitudinal direction and protrudes somewhat out of'refill ll. Around its circumference the cylindrical, body 7 is provided with one or more longitudinal grooves 8 for the inlet of the surrounding air into the inner space of the refill shell. One end of valveclosure spring 5 is seated against the forward end of valve disk 3 and the other end is seated on a bead-shaped embossing of the refill shell 1 which forms a ring-shaped spring seat h. At a distance from the front writing end 2 of the refill shell 1 a cross section reduction means in the writing medium reservoir is protube; and guide member and-detent means on the. ball vided consisting of a partition lit! with capillary llongitudinal grooves ill at its circumference as capillary passages, This is to be inserted into the refill shell 1 prior to filling it with the writing medium. This partition 10 subdivides the writing medium reservoir into section 13 behind the writing ball point and a writing medium storage section 12, whereby the longitudinal capillary grooves 11 on the circumference of the partition allow only a much delayed passage of the writing medium from the writing medium section 13 to the writing medium storage section 12 if the ball point pen is used for writing in a position where the chamber is below the forward writing end 2.

Refill shell or tube 1 is provided with abutment flange 14 which is formed by the abutting flanges of the two adjacent hollow tubular parts of the refill shell. Flange 14 serves as an abutment for valve spring 16 which is abutted at its other end on a forward portion 15 of the casing. Spring 16 serves to urge refill shell 1 rearwardly to the non-writing with the writing end thereof retracted a short distance into the casing.

A detent means generally designated as 28 is provided at the rear of the casing to prevent rearward movement of the cylindrical body or guide means 7 and the spindle valve with respect to the casing. In this embodiment detent means comprises pressure plate 18 seating on guide means 7 and fixed to a cylindrical shaft 29 extending through and slidably engaged in the rear end of the casing 1. Projection 31 on shaft 29 engages the rear end of the casing and prevents rearward movement of the detent means. Groove 30' in the rear end of the casing adjacent shaft 29 is provided to receive projection 31 when shaft 29 is rotated by means of handle 32 so that projection 31 is immediately therebelow. At this position shaft 29 is free to move upwardly until detent 31 engages the upper end of recess 30. Since spring 16 urges refill 1 upwardly against detent means 28, when shaft 29 is rotated to this position, detent means 28 and refill 1 will move rearwardly to non-writing position. To move the refill back to writing position, shaft 29 is pushed forwardly and rotated to disengage projection 31.

In writing, the pressure of the pen on the paper moves refill 1 towards the rear against spring 5 while the spindle valve is held stationary with respect to the pen casing. Thus valve seat 4 is moved from the valve disk 3 to allow air to enter into the writing medium chamber storage section 12.

In the embodiment of FIGURE 2, the detent means at the rear end of the casing for preventing relative movement of a spindle valve and guide means with respect to the casing is simply the rear end of the casing itself. In this embodiment the valve closure spring 5 is placed rearwardly of valve seat 4 to surround spindle 6 and to extend between and abut against valve seat 4 and cylindrical guide member 7. Guide member 7 removably and longitudinally adjustably receives the upper end of spindle 6 by means of cooperating threads 20 on spindle 6 and in guide member 7.

Valve seat 4 is a bead-shaped inward circular boss. Not only is its forward side used as a valve seat but its rearward side serves as a seat for spring 5.

Guide member 7 is again received and guided loosely by refill shell 1 and is provided on its circumference with longitudinal grooves 8 for passage of air from the outside to communicate with the valve and thus the writing medium chamber. Guide member 7 is provided at its outer end with a transverse groove 21 for receiving an adjustment tool as for instance a screw driver for screwing the guide member with respect to valve spindle 6 to adjust the tension on valve closure spring 5.

In the same manner the valve disk 3 which has preferably a conical seat is provided on its cylindrical extension 22 with a transverse slot 23 for the introduction of a screw driver when screwing the valve spindle 6 into the thread 20 of the cylindrical body 7.

Instead of the partition 10 in FIG. 1 there is provided in FIG. 2 in the refill shell 1 between the writing medium space 13 and. the writing medium storage space 12 a bead-shaped annular boss 24 which has an impeding effect on the passage of the writing medium from the writing medium space 13 to the writing medium storage space 12 and which exercises a more or less strong throttling action on the writing medium.

In FIG. 3 the annular boss for the valve seat 4 is executed-as a groove with a middle hollow cylindrical part 25 with reduced diameter and conical end transition surfaces 4. The limit stop surface 26 for the valve closure spring 5 is represented by punched in conical projections 26 distributed around the circumference of the refill sleeve 1. The partition 10 is fixed in its position by means of small radial conical projections 27.

The bead-shaped embossings 4, 9, 24 and 25 can be made tapering or conical or cylindrical. The valve disk 3 can likewise be provided with conical or flat annular seat surfaces. The refill shell 1 can be inserted into the ball point pen casing rigidly or between counteracting springs, so that in writing the refill shell is under spring influence and yields elastically, so that it is possible to write with thicker or thinner lines.

It is to be pointed out that the refill inherently yields elastically to some extent, anyway. The refill will yield backwardly in the casing during writing against valve spring 5 to an extent which varies with the stiffness of spring 5.

The bead-shaped annular boss can also be executed as prickmade projections or prick projections 26 of conical shape distributed all over the circumference of the refill sleeve, particularly when they are only used as limit stops for thespring 5. The partition body 10 can be fixed on the wall of the refill sleeve 1 by prick-made projections.

What I claim is:

1. In a ball point pen, a casing, a tube-like ball point refill longitudinally slidably received by said casing, a forward opening in said casing for receiving the forward writing end of said refill therethrough in writing position, detent means on said casing holding said refill from moving forward beyond said writing position in said casing, said refill comprising a tube, a forward writing end on said tube having a ball point thereon, a valve seat in said tube rearwardly of said writing end, a spindle valve in said tube forward of said valve seat with the spindle extending rearwardly through said valve seat, said valve seating rearwardly in said valve seat to close ofl. the tube, means on said tube extending to said valve for biasing said valve rearwardly in said tube to seated position, a cylindrical guide member mounted on said spindle rearwardly of said valve seat and longitudinally slidably mounted in said tube for guiding said valve in and out of seating engagement with said valve seat, said guide member having air inlet passages extending therethrough and detent means on said casing seating on and operating against the rearward end of said guide member to hold said guide member and spindle valve connected thereto against rearward movement with respect to said casing and thus to hold said refill in forward writing position, whereby, when the writing end of said refill is pressed against the paper, said refill tube and said valve seat thereon are displaced rearwardly against said biasing means to open said valve.

2. A ball point pen as in claim 1 wherein said biasing means includes a spring seat inside said tube rearwardly of said valve seat and a compression spring seated on said spring seat extending to and seated against the forward end of said cylindrical guide member.

3. A ball point pen as in claim 2 wherein the rearward end of said spindle is screwably received by said guide member for longitudinal adjustment therewith, the forward end of said valve and the rearward end of said guide member being provided with screw head means for cooperation with a screwing adjustment tool.

4. A ball point pen as in claim 2 wherein the rearward side of said valve seat serves as said spring seat.

5. A ball point pen as in claim 4 wherein said valve seat comprises an inwardly extending annular boss on said tube.

6. A ball point pen as in claim 1 wherein said tube forward of said valve seat comprises a writing medium chamber, connected to and communicating with said forward writing end, a forward writing end reservoir section in said chamber adjacent said forward writing end, a storage section in said chamber and a partition between said storage section and said reservoir section having a plurality of capillary passages therethrough to provide restricted writing medium communication between said sections.

7. In a ball point pen, a casing, a tube-like ball point refill longitudinally slidably received by said casing, a forward opening in said casing for receiving the forward writing end of said refill therethrough in writing position, detent means on said casing holding said refill from moving forward beyond said writing position in said casing, said refill comprising a tube, a forward writing end on said tube having a ball point thereon, a valve seat in said tube rearwardly of said writing end, a spindle valve in said tube forward of said valve seat with the spindle extending rearwardly through said valve seat, said valve seating rearwardly in said valve seat to close off the tube, valve guide means on said spindle for guiding said valve in and out of seated position, a spring seat in said tube forward of said valve seat, said spring seat comprising an inwardly extending annular boss on said tube, a compression spring seated on said spring seat extending rearwardly to and seated against the forward end of said valve for biasing said valve to seated position and detent means on said casing operating against said spindle valve to hold said spindle valve against rearward movement with respect to said casing and thus to hold said refill in forward writing position, whereby, when the writing end of said refill is pressed against the paper, said refill tube and said valve seat thereon are displaced rearwardly against said spring to open said valve.

References Cited in the file of this patent UNITED STATES PATENTS 1,862,586 Vivian June 14, 1932 2,489,976 Perwas Nov. 29, 1949 2,883,969 Sams Apr. 28, 1959 FOREIGN PATENTS 252,969 Germany Oct. 31, 1912 449,928 Italy Oct. 31, 1947 926,055 France Apr. 14, 1947 971,021 France June 28, 1950 OTHER REFERENCES German application S33630X/70b, printed August 30, 1956. 

